Gauge field theory without groups

Non-standard topics underlying a partly original approach to gauge field theory are concisely introduced, expressing ideas that were broached in several papers and, eventually, exposed in an organized form in a recently published book. By proposing a change of perspective about the roles and relative importance of several notions, this approach seeks to obtain an overall clarification of foundational matters. In particular, by consistently relying on natural differential geometry, the role of groups is shown to be downgradable to secondary.